Human brain is the most mysterious machine in nature. We hardly know anything about it. Scientists from UCL and University of Oxford have just found that when we’re resting our brains spontaneously replay our experiences. This may be the basis of our powerful reasoning abilities.
That is why having experience is important. You can make predictions about new situations based on your previous experiences. This allows making broad assumptions when we are faced with little information and avoiding trouble that we’ve gotten ourselves into in the past. Scientists found that to organize these memories brain replays them at rest.
Researchers invited a number of participants to complete a task. At first scientists trained them in a task defining an ordering of everyday objects. Then participants were given a task to do the same with a new set of familiar objects in a scrambled order. Meanwhile scientists applied MEG neuroimaging to map participants’ brain activity. Scientists were able to observe replay events happening – new experiences were relived in the brain in fast forward fashion. Also, events were played in a different order than they happened in real life, which shows that brain was actually organizing experiences.
Timothy Behrens, co-author of the study, said: “A defining feature of human intelligence is the ability to make strong inferences on the basis of sparse observations. If you notice your husband’s wallet on the kitchen table, you immediately know he is more likely to be in the garden than the pub. It is completely unknown how such inferences are performed in our brains, but our research suggests an important role for replay”.
Finally, scientists found that the replay is actually factorized – some parts of some experiences are replayed over and over again. Scientists say that factorized representations are a powerful means of generalising knowledge. This makes it easier to later apply this newly acquired knowledge. New situations do not have to match perfectly with our past experiences, which means that our memories are easier to apply in decision making processes. Individual experiences are decomposed into parts, which can be recombined in a number of ways. As long as some of these combinations somewhat match new circumstances, we know what we’re going to do. This may be useful in a broad array of cognitive tasks.
Flexibility of our memory is a great tool, which allows making faster, better informed decisions. Understanding how human memory works can push scientists closer to solving some issues associated with it. For example, memory loss. It will also improve our understanding of our own decision making processes and something we call “intuition”.